Near field distributions in radial line slot antennas for surface wave coupled plasma generation

The near field distributions in radial line slot antennas (RLSA) for surface wave coupled plasma (SWP) are examined. The RLSA are suitable for uniform, high density and large-area plasma generation. In order to realize higher productivity, quick evacuation of reaction gas a narrow gap process space is highly required. Since a wafer is placed close to the antenna aperture in this case, the evaluation of the electromagnetic near-fields in the RLSA for the plasma process is effective and indispensable. Plasma distribution control by changing the slot pattern is also possible based upon the information of the near field distributions. A novel slot pattern, which has many transverse slots, is fabricated and tested. The exponential attenuation of the fields in the boresight direction is measured and the interesting and remarkable characteristics of the novel RLSA for SWP process are confirmed.